We sought to identify metabolites that were overrepresented in the metabolic networks of taxa, that were themselves assigned extreme entries along diffusion map variables. This was accomplished using a permutational analysis analogous to the gene set enrichment analysis, GSEA [1]}. Genome rankings were provided by the orderings specified by each diffusion variable. Enrichment analyses were accomplished for the preranked sets using the fgsea library in R, with an FDR-adjusted \(P\) -value \(< 0.05\)  used as the threshold for retaining metabolites associated with taxa that map to variable extrema.
